Capillary Pressure and Relative Permeability Model Uncertainties in Simulations of Geological CO2 Sequestration

摘要

Precise descriptions of saturation, capillary pressure and relative permeability s-pckr relations are essential for predictions and simulations on multiphase flow system. The primary object of this work is to investigate their influence on geological CO2 sequestration processes. Five types of commonly used s-pc-kr relations are examined in this study. Simulation results show significant influences of s-pc-kr relations on 1) the location and saturation of displacement fronts, 2) buoyancy driven migration speed, 3) horizontal spreading distance and the rate of dissolution of supercritical CO2. The effects of capillary pressure on the horizontal spreading of supercritical CO2 plume and its dissolution rate was resolved in this study for the 1st time in literatures. Simulation results of subsurface CO2 storage suggest that that careful selection of s-pc-kr relations and calibration methods are essential for accurate predictions.